Method of and apparatus for removing nonliquid constituents from fuel oil



Aprxl 13, 1965 P. ARANT 3,1

METHOD OF AND APPARATUS FOR REMOVING NONLIQUID CONSTITUENTS FROM FUELQIL Filed Sept. 30, 1960 BURNER lA/l/EA/ 702 R522 Y A RA 1v 7' 5y #4? Arrozmsrs HARP/3- K/Ecw, R0555 d: KER/V United States Patent 3,177,919METHOD OF AND APPARATUS FOR REMOVING NONLIQUID CONSTITUENTS FROM FUELOIL Perry Arant, San Gabriel, Ca1if., assignor to Clayton ManufacturingCompany, El Monte, Calif., a corporation of California Filed Sept. 30,1960, Ser. No. 59,725 7 Claims. (Cl. 15836.3)

The present invention relates in general to a method of and apparatusfor removing from liquids any non-liquid constituents, such as vapors,entrained gases, foam, and the like, which may be present therein. Morespecifically, the invention is particularly applicable to removing fromheavy fuel oils such nonliquid constituents as entrained air, or othergases, vapors which flash out at elevated temperatures, foam produced byvaporization of moisture at elevated temperatures and variablepressures, and the like.

In general, the invention contemplates an oil burning installation,which may be a steam generator, for example, wherein fuel oil drawn froma storage reservoir is heated prior to delivery to the burner to obtainproper combustion. It is also essential to proper combustion that thefuel oil consumed by the burner be relatively free from entrained air,or other gases, vapors, foam, and the like, and a primary object of theinvention is to provide a method and apparatus which will achieve thiscondition.

An important object of the invention is to provide an apparatus forseparating nonliquid constituents from the fuel oil which incorporatesseparate storage and burner circuits so that the oil delivered to theburner nozzle may be heated accurately to the temperature necessary toobtain the desired viscosity.

A more specific object of the invention isto provide a separatingapparatus which is interposed between the storage reservoir and theheater and burner system and which returns separated air, or othergases, vapors and foam to the reservoir. A related object is to compressany foam to liquid before returning it to the reservoir, and to cool allgases, vapors and liquid returned to the reservoir to a temperaturebelow the flash temperature of the liquid, but without cooling themexcessively so as to avoid unnecessary heat loss.

An important object is to provide an installationwherein a surplus offuel oil is delivered to the separating apparatus by a transfer meansand wherein an excess of fuel oil is delivered to the heater and burnersystem by a fuel supply means, the excess liquid delivered to the heaterand burner system by the fuel supplymeans being returned to theseparating apparatus and surplus liquid being returned to the reservoirfrom the separating apparatus along with any liberated air, or othergases, vapors, foam and the like.

Another object is to provide a separating apparatus which includes gasseparating means for removing entrained air, or other gases, from thefuel oil delivered to the separating apparatus by the transfer means.

A further object is to provide means for removing vapors and foam fromthe excess liquid returned to the separating apparatus by the heater andburner system.

An important object of the invention is to return to the heater andburner system the excess fuel oil discharged thereby, after removal ofvapors and foam therefrom, in admixture with a fresh supply of fuel oilfrom the gas separating means. As the result of this recycling of theexcess liquid from the heater and burner system, the fuel oil actuallyconsumed by the burner is relatively free from entrained gases, vapors,foam and thelike, which isan important feature.

Another object of the invention is to provide a separat ing apparatushaving means for compressing the foam 3,177,919 Patented Apr. 13, 1965"ice removed by the vapor separating means prior to returning same tothe reservoir.

Still another object is to provide a separating apparatus having asection which cools separated vapors sufficiently to reduce thetemperature of any gases, vapors, compressed foam and surplus liquid toa temperature below the flash temperature of the fuel oil before returnto the reservoir, but Without excessively cooling same so as to minimizeany heat loss from the over-all installation.

The foregoing objects, advantages, features and results of the presentinvention, together with various other objects, advantages, features andresults thereof which will be evident to those skilled in the art towhich the invention relates 'in the light of this disclosure, may beachieved with the exemplary embodiment of the invention described indetail hereinafter and illustrated in the accompanying installationwhich incorporates the separating apparatus of the invention; and

FIG. 2 is a detail view duplicating a portion of FIG. 1 on an enlargedscale.

In the drawing, the numeral lfi designates generally a separatingapparatus of the invention interposed between a storage reservoir 12 anda heater and burnerjsystem 14 comprising a heater 16 and a burner'18.The reservoir 12 may be of any desired nature and may, for example, bean underground storage tank. The heater and burner 16 and 18 may also beof any suitable types and are therefore shown only diagrammatically. Theburner 18, of course, includes a suitable burner nozzle, control meansfor regulating the delivery of fuel oil to the burner nozzle, a fuelpressure regulator, and the like, such components being conventional sothat a showing thereof is not necessary. For example, the control meansmay comprise a low fire valve and a high fire valve, as is conventional.

More particularly, the separating apparatus 10 includes: a separatingassembly 20; transfer means 22, including a transfer pump 24, fortransferring fuel oil, including a surplus of 'fuel oil, to theseparating assembly 20;.fuel supply means 26, including a fuel pump 28,for delivering an excess of fuel oil to the heater 16 and thence to theburner 18; first return means 30 for returning the excess fuel oil fromthe heater and burner system 14 to the separating assembly'20;'andsecond return means 32 for returning "constituents separated out by theseparating assembly 20 and surplus fuel oil to the reservoir 12. Theseparating assembly 20 itselfincludes: gas separating means 34 forremoving entrained gases from the fuel oil delivered to the separatingassembly by the transfer means 22; vapor separating means 36 forremoving vapors and foam from the excess liquid returned to theseparating assembly. from the. heater and burner system 14 by the firstreturn means .30; recycling means 38 for returning to theheater andburner system 14 the excess liquid emanating therefrom, after removal ofvapors and foam, in admixture with fresh fuel oil from which entrainedgases have been removed; cooling means 40 for sufficiently coolingvapors separated out by the vapor separating means 36 that the mixturereturned to thereservoir 12 by the second return means 32 will be at atem- 3' right gas separator chamber 50, which may have .the form of aslender cylindrical tank as shown. The chamber 50 is provided at itslower end with a drain plug 52. The separating assembly 20 also includesan upright vapor separator chamber 54 alongside the gasseparator chamber50, the vapor separator chamber being shown as of smaller diameter thanthe gas separator chamber. The upper and lower ends of the vaporseparator chamber 54 communicate with the gas separator chamber 50,adjacent the upper and lower ends of the latter, at vertically spaced,upper and lower zones 56 and 58.

The transfer means 22 includes a transfer line 60 in which the transferpump 24 is connected and the inlet end of which is connected to asubmerged bell-shaped heater62within the reservoir 12. The heater 62maintains the fuel oil in the vicinity of the inlet end of the transferline 60 at a temperature of, for example, the order of magnitude of 100F. Thus, the heater 62 preheats the fuel oil drawn into the transferline 60 by the transfer pump 24. The outlet end of the transfer line 60communicates with the gas separator chamber 50 at a zone 64 intermediatethe upper and lower zones 56 and 58 of interconnection between the gasand vapor separator-chambers 50 and 54. V

The capacity of the transfer pump 24 is of the order of one and one-halfto two times the capacity of the fuel pump 28 so that the transfer pumpintroduces a surplus of fuel oil into the gas'separator chamber 50, suchsurplus ultimately being returned to the reservoir 12 by way of thereturn means 32. The remainder of the fuel oil introduced by thetransfer pump 24flows downwardly in the gas separator chamber 50 to thefuel supply means 26 leading to the heater and burner system 14. Thecross sectional area of the gas separator chamber 50 is several timesthat of the transfer line 60 so that the downflow of fuel oil from thezone 64 to the zone 58 takes place at relatively low velocity.Consequently, the downflowing fuel oil liberates any air, or othergases, entrained therein, such entrained air or gases rising in the gasseparator chamber 50 and ultimately being returned vto the reservoir 12by way of the return means 32, along with the aforementioned surplusfuel oil. The relatively air and gas free oil in thegas-separator-chamber zone 58 enters the fuel supplymeans 26, comprisinga fuel line 66in which the fuel pump 28 is connected and which leadstothe heater 16. The heater, of course, is connected to the burner 18, asby a fuel risers; 1 L

The capacity of the fuel pump 28 exceeds the maximum rate of fuelconsumption of the burner 18. For example, the capacity of the fuelpump. 28 may be of the order of twice the maximum fuel consumption rateof the' burner 18. .Consequently, the fuel pump 28 delivers an excess offuel oil to the burner 18. v f

This excess of fuel oil delivered to the burner 18 flows from the fuelpressure regulator of the burner to the vapor separator chamber. 54.byway of the return means 30, which is shown as comprising simply a returnline 70 extending from'the fuel pressure regulator of the burner to thevapor separator chamber 54 at a zone 72 intermediate the upper and lowerzones 56. and 58 of connection between the gas and vapor separatorchambers 50 and 54.

Since the excess oil returned to the vapor, separator chamber 54 throughthe return line 70 is at an elevated temperature because of its passagethrough the heater 16, and since the excess oilis reduced in pressure asit is returned to the vapor separator chamber, vapors, residual air andother gases, and foam are liberated within the vapor:separator chamber,the foam resulting from vaporization of moisture which may be present inthe fuel oil. Such vapors, air and other gases, and foam pass upwardlythrough the vapor separator chamber 54 into the upper end of the gasseparator chamber 50 for ultimate return to the reservoir 12 by way ofthe return means 32. The hot excess oil itself flows downwardly throughthe vapor separator chamber 54 back into the fuel line 66, such downflowassisting in the separation of vapors, air and other gases, and foam. Asshown in FIG. 1, the fuel line 66 communicates with the chamber 54 abovethe lower zone 58 of interconnection between the chambers 50 and 54 toprevent flow of the hot excess oil from the burner 18 into the gasseparator chamber.

Thus, the hot excess oil, now relatively free of vapors, air and othergases, and foam, is returned to the burner 18 by the fuel pump 28, alongwith make-up fuel oil, which is relatively free of entrained air andother gases, from the gas separator chamber 50.

This recycling of the excess fuel oil emanating from the burner 18,supplemented by make-up fuel oil from the gas separator chamber 50,results in a flow of fuel oil to the burner which is relatively freefrom entrained air, or other gases, vapors, foam and the like.Consequently, there is minimum interference with proper burner operationby the presence of nonliquid constituents in the fuel oil actuallydelivered to the burner nozzle. Also, since the heater circuit isseparated from the storage transfer circuit, accurate control of thetemperature, and;

I therefore the viscosity, of the oil actually delivered to the burnernozzle is possibleto insure optimum operating conditions at the burner18.

The vapor separator chamber 54 communicates with the gas separatorchamber 50 in the upper zone 56 through an orifice 74 constituting thefoam compressing means 42. The orifice 74, by serving to restrict theflow of foam into the gas separator chamber 50, reduces a major portion,e.g., approximately 80%, 0f the foam to liquid form prior to entrythereof into the gas separator chamber, which is an important feature.The gas separator chamber 50 is provided therein with a cleanout plug 76for the orifice 74 located opposite this orifice.

The upper portions of the gas and vapor separator chambers 50 and 54serveto cool the vapors separated out in the vapor separator chambersufliciently that the fluid mixture returning to the reservoir 12 is ata temperature below the flash temperature of the fuel oil in thereservoir. Thus, the upper portions of the gas and vapor separatorchambers 50 and 54 constitute the cooling means 40 hereinbeforementioned. 7

The surplus fuel oil introduced into the gas separator chamber 50 by thetransfer pump 24, entrained air and other gases liberated in the gasseparator chamber 50, and air and other gases, vapors, and reduced foamfrom the vapor separator chamber 54, are all returned to the reservoir12 by way of the return means 32.: This return means includes a returnline 78 in which the pressure relief valvemeans 44 is located and theinlet end of which communicates with the gas separator chamber 50 belowthe upper zone 56 of interconnection between the gas and vapor separatorchambers 50 and 54, but above the zone 64 of interconnection between thegas separator chamber 50 and the transfer means 22.

The pressuer relief valve means 44, which may be of any suitableconstruction, maintains a small back pressure, e.g., 5 p.s.i., on theseparating assembly 20, such back pressure performing two functionsFirst, the back pressure applied by the relief valve means 44 completesthe reduction to liquid of any foam separated out in the by the transferpump 24.

Although an exemplary embodiment of the invention 113 e n isclosedherein for purposes of illustration, 1t

ears s19 will be understood that various changes, modifications andsubstitutions may be incorporated in such embodiment without departingfrom the spirit of the invention as defined by the claims which follow:

1.A method of separating gases from fresh fuel oil obtained from areservoir and delivered to a heater and burner system which heats fueloil delivered thereto, which burns only part of the fuel oil deliveredthereto, and which discharges the remainder of the fuel oil deliveredthereto as heated exces fuel oil, and of separating vapors from saidheated excess fuel oil, including the steps of:

(a) removing gases from said fresh fuel oil being delivered to theheater and burner system from the reservoir;

(b) removing vapors from said heated excess fuel oil;

(0) then mixing said heated excess fuel oil from which vapors have benremoved with said fresh fuel oil from which gases have been removed; and

(at) then returning said heated excess fuel oil from which vapors havebeen removed to said heater and burner system admixed with said freshfuel oil from which gases have been removed.

2. A method of separating gases from fresh fuel oil obtained from areservoir and delivered to a heater and burner system which heats fueloil delivered thereto, which burns only part of the fuel oil deliveredthereto, and which discharges the remainder of the fuel oil deliveredthereto as heated excess fuel oil, and of separating vapors from saidheated excess fuel oil, including the steps of:

(a) removing gases from said fresh fuel oil being delivered to theheater and burner system from the eservoir;

(b) removing vapors from said heated excess fuel oil;

(c) then mixing said heated excess fuel oil from which vapors have beenremoved with said fresh fuel oil from which gases have been removed;

(d) then returning said heated excess fuel oil from which vapors havebeen removed to said heater and burner system admixed with said freshfuel oil from which gases have been removed;

(e) cooling the vapors removed from said heated excess fuel oil; and

(f) returning to the reservoir the cooled vapors removed from saidheated excess fuel oil and the gases removed from said fresh fuel oil.

3. A method of separating gases from fresh fuel oil obtained from areservoir and delivered to a heater and burner system which heats fueloil delivered thereto, which burns only part of the fuel oil deliveredthereto, and

which discharges the remainder of the fuel oil delivered thereto asheated excess fuel oil, and of separating vapors and foam from saidheated excess fuel oil, including the steps of:

(a) removing gases from said fresh fuel oil being delivered to theheater and burner system from the reservoir;

(12) removing vapors and foam from said heated excess fuel oil;

(0) then mixing said heated excess fuel oil from which vapors and foamhave been removed with said fresh fuel oil from which gases have beenremoved;

(d) then returning said heated excess fuel oil from which vapors andfoam have been removed to said heater and burner system admixed withsaid fresh fuel oil from which gases have been removed;

(e) cooling the vapors and foam removed from said heated excess fueloil;

(f) compressing the foam removed from said heated excess fuel oil; and

(g) returning to the reservoir the cooled vapors and the cooled andcompressed foam removed from said 5 heated excess fuel oil, and thegases removed from said fresh fuel oil.

4. An apparatus for separating nonliquid constituents from f tel oildelivered to a heater and burner system which heats fuel oil deliveredthereto, which burns only part of the fuel oil delivered thereto, andwhich discharges the remainder of the fuel oil delivered thereto asheated excess fuel oil, said apparatus being positionable between andconnectible to the heater and burner system and a reservoir containingfresh fuel oil, and including:

(a) a closed, upright gas separator chamber;

(b) a closed, upright vapor separator chamber communicating with saidgas separator chamber in vertically spaced, upper and lower zones ofsaid gas separator chamber;

(0) transfer means, connectible to the reservoir and including atransfer pump, for delivering fresh fuel oil from the reservoir to saidgas separator chamber intermediate said upper and lower zones thereof;

(d) means, including a second pump communicating with said gas and vaporseparator chambers adjacent said lower zone of said gas separatorchamber and connectible to the heater and burner system, for deliveringfuel oil to the heater and burner system;

(e) first return means connectible to said heater and burner system andcommunicating with said vapor separator chamber intermediate said upperand lower zones of said gas separator chamber for returning said heatedexcess fuel oil discharged by the heater and burner system to said vaporseparator chamber; and

( second return means connectible to the reservoir and communicatingwith said gas separator chamber below said upper zone thereof, and abovethe zone at which said transfer means communicates with said gasseparator chamber, for returning to the reservoir nonliquid constituentsremoved from the fresh fuel oil in said gas separator chamber and fromsaid heated excess fuel oil in said vapor separator chamber.

5. A. separating apparatus as defined in claim 4 wherein said secondreturn means includes pressure relief valve means for maintaining apredetermined back pressure on said gas separator and vapor separatorchambers.

6. A separating apparatus as set forth in claim 5 including meansproviding a restriction to flow from said vapor separator chamber intosaid gas separator chamber in said upper zone of said gas separatorchamber.

7. A separating apparatus according to claim 6 wherein said transferpump has a pumping capacity greater than the pumping capacity of saidsecond pump, and wherein said second pump has a pumping capacity greaterthan the maximum fuel-oil combustion rate of the heater and burnersystem. 7

References Cited by the Examiner UNITED STATES PATENTS 2,252,687 8/41-Bassett 137--202 2,277,100 3/42 Hartmann 55-201 2,290,350 7/42 Olches158-36.3 X 2,482,806 9/49 Stahn 55-417 2,510,190 6/50 Nicolette 55199 X2,721,621 10/55 Hall 55-186 2,878,889 3/59 Gilbert 55-204 2,901,031 8/59Powell et al. 55199 3,073,376 1/63 Hobson 15836.3

FOREIGN PATENTS 478,449 1/38 Great Britain.

NORMAN YUDKOFF, Primary Examiner.

REUBEN FRIEDMAN, FREDERICK MATTESON,

WALTER BERLOWITZ, Examiners.

4. AN APPARATUS FOR SEPARATING NONLIQUID CONSTITUENTS FROM FUEL OILDELIVERED TO A HEATER AND BURNER SYSTEM WHICH HEATS FUEL OIL DELIVEREDTHERETO, WHICH BURNS ONLY PART OF THE FUEL OIL DELIVERED THERETO, ANDWHICH DISCHARGES THE REMAINDER OF THE FUEL OIL DELIVERED THERETO ASHEATED EXCESS FUEL OIL, SAID APPARATUS BEING POSITIONABLE BETWEEN ANDCONNECTIBLE TO THE HEATER AND BURNER SYSTEM AND A RESERVOIR CONTAININGFRESH FUEL OIL, AND INCLUDING: (A) A CLOSED, UPRIGHT GAS SEPARATORCHAMBER; (B) A CLOSED, UPRIGHT VAPOR SEPARATOR CHAMBER COMMUNICATINGWITH SAID GAS SEPARATOR CHAMBER IN VERTICALLY SPACED, UPPER AND LOWERZONES OF SAID GAS SEPARATOR CHAMBER; (C) TRANSFER MEANS, CONNECTIBLE TOTHE RESERVOIR AND INCLUDING A TRANSFER PUMP, FOR DELIVERING FRESH FUELOIL FROM THE RESERVOIR TO SAID GAS SEPARATOR CHAMBER INTERMEDIATE SAIDUPPER AND LOWER ZONES THEREOF; (D) MEANS, INCLUDING A SECOND PUMPCOMMUNICATING WITH SAID GAS AND VAPOR SEPARATOR CHAMBER AND SAID LOWERZONE OF SAID GAS SEPARATOR CHAMBER AND CONNECTIBLE TO THE HEATER ANDBURNER SYSTEM, FOR DELIVERING FUEL OIL TO THE HEATER AND BURNER SYSTEM;(E) FIRST RETURN MEANS CONNECTIBLE TO SAID HEATER AND BURNER SYSTEM ANDCOMMUNICATING WITH SAID VAPOR SEPARATOR CHAMBER INTERMEDIATE SAID UPPERAND LOWER ZONES OF SAID GAS SEPARATOR CHAMBER FOR RETURNING SAID HEATEDEXCESS FUEL OIL DISCHARGE BY THE HEATER AND BURNER SYSTEM TO SAID VAPORSEPARATOR CHAMBER; AND (F) SECOND RETURN MEANS CONNECTIBLE TO THERESERVOIR AND COMMUNICATING WITH SAID GAS SEPARATOR CHAMBER BELOW SAIDUPPER ZONE THEREOF, AND ABOVE THE ZONE AT WHICH SAID TRANSFER MEANSCOMMUNICATES WITH SAID GAS SEPARATOR CHAMBER, FOR RETURNING TO THERESERVOIR NONLIQUID CONSTITUENTS REMOVED FROM THE FRESH FUEL OIL IN SAIDGAS SEPARATOR CHAMBER AND FROM SAID HEATED EXCESS FUEL OIL IN SAID VAPORSEPARATOR CHAMBER.